Method of producing brake drums



Aug. 23, 1938. H. J. HORN 2,127,597

METHOD PRODUCI NG BRAKE DRUMS Original Filed March 18, 1935 2 Sheets-Sheet 1 INVENTOR. HAPPY J HOE/V ATTORNEY.

Aug. 23, 1938.

H. J. HORN 2,127,597

METHOD OF PRODUCING BRAKE DRUMS Original Filed March is. 1955 2 Sheets-Sheet 2- ATTORNEY.

Patented Aug. 23, 1938 UNITED STATES PATENT OFFICE Harry J. Horn,

Wheel Corporation, Lansing,

tion of Michigan Original application March 18, 11,609. Patent N0. 2,038,84

Lansing, Mich, assignor to Motor Mich., a corpora- 1935, Serial No. dated April 28,

1936. Divided and this application March 23, 1936, Serial No. 70,309

2 Claims.

This invention relates to a method of producing brake drums of the type wherein the brake ring and the supporting web therefor are formed separately and then secured to each other to form a composite brake drum. The present application is a division of my co-pending application Serial No. 11,609, filed March 18, 1935, for Brake drums and the method of producing brake drums, issued April 28, 1936, as Patent No. 2,038,842.

The principal object of this invention is to produce such a composite brake drum from a minimum amount of material without impairing the necessary characteristics of rapid heat dissipation and sturdiness required in brake drums under present conditions of use. The manner in which this and other objectives are obtained will more fully appear from the following description taken in connection with the drawings forming a part hereof.

In the drawings:

Figures 1 to 8 inclusive illustrate the various steps in the production of the supporting web;

Figure 9 is a fragmentary front view of the brake ring prior to assembly with the web;

Figure 10 is a partial sectional view of the ring and web after assembly and before being fastened together;

Figure 11 illustrates the manner in which the extremities of the integral projections of the web are deformed to fasten the ring and web together;

Figure 12 is a sectional view taken on substantially the line l2l2 of Figure 11;

Figure 13 is a partial front view of the composite drum after the ring and web have been secured to each other as illustrated in Figure 11;

Figure 14 is an enlarged fragmentary view of the composite drum of Figure 13 showing the relation of the projections carried by the web and the ring; and

Figure 15 is a partial sectional view of the composite drum taken on substantially the line I5-I5 of Figure 13.

The present method will best be understood by first referring to the illustration in Figures 13 and 15 of the completed composite drum. In these figures the drum is shown as consisting of a brake ring I0 having an inturned flange H at one edge thereof. The ring is here shown as of the type having a wear-resisting inner liner l2. The external surface of the ring In is preferably deformed as indicated at I3 to provide a stiffening means adjacent the open side thereof. The flange ll of ring I0 is provided with circumferentially spaced apart rectangular openings I4 which are best shown in Figure 9.

The ring I0 is supported by a generally disklike web [5. The web is provided with a plurality of integral fingers It at its periphery (see Figure 10). The fingers it are rectangular in cross section, the cross sectional area thereof being slightly less than the area of theopenings M. The fingers [6 project through the corresponding openings M in the ring flange II and have their free extremities enlarged as indicated at I! in Figures 11, 12, 13 and 14. The manner in which these fingers are enlarged to overlie the edges of the cooperating openings M will be described presently.

The web I5 is provided with a central opening [8 in order to mount the same over a wheel hub such as that shown in dotted lines in Figure 15. Adjacent the central opening It the hub is provided with ,a series of relatively large holes I9 and an intermediate series of relatively smaller holes 20. The smaller holes are utilized in attaching the web to a hub flange as by riveting and the larger holes l9 are aligned with corresponding holes in the hub flange and receive the securing studs by means of which a wheel may be attached to the hub flange.

The ring l0 and the web ll: of the brake drum illustrated in Figures 13 and 15 are produced separately. The ring H! is here shown as of the type preferably formed from strip stock rolled into a hoop with the ends welded together. The ring is formed with the flange H at one end thereof and the flange is provided with the openings I4. The wear-resisting inner liner l2 may be of any desired material such as cast iron for example, and may be secured to the ring by a centrifugal casting process.

The formation of the web I5 is diagrammatically illustrated in Figures 1 to 8 inclusive. Initially a series of disks are cut from a rectangular blank of metal (Figure 1). Preferably at the same time the disks are struck from the blank they are also subjected to a deforming operation by means of which the disk is deformed to provide a central portion 15a and a peripheral portion |5b lying in spaced parallel planes. Suitable dies for effecting these blanking and drawing operations simultaneously are shown in Figure 2.

The disk I5 is next subjected to the die operation diagrammatically illustrated in Figure 4 to form the annular rib 26 at the inner extremity of the peripheral portion I517. Thereafter, the edges of the peripheral portion 15b are cut away to produce the circumferentially spaced apart integral projections [6 of rectangular cross section. The cross sectional area of the projections I6 is slightly less than the area of the openings I4 in flange H of ring ill (see Figure 9). The main diameter of the disk l5 after the formation of the projections I6 is such as to locate its periphery radially inwardly of the openings i l in flange I I of ring H3 when the ring and web are assembled as hereinafter described.

Preferably at the same time the projections l6 are formed, the central portion l5b of the disk is pierced to produce the openings I8, 19 and 2E). Suitable dies for performing these last mentioned operations are diagrammatically illustrated in Figure 5. Figure 6 shows a fragmentary front View of the disk I5 after it has been subjected to the die operations illustrated in Figure 5.

The projections it are bent laterally through an arc of substantially degrees in order that they may be inserted through the openings M in the flange H of ring it when the ring and web are assembled. Where it is desired that the fingers formed from projections l6 extend in a truly axial direction they are bent in a single operation as graphically illustrated in Figure 7.

It has been found that the best results are obtained by bending the projections it at a point a slight distance outwardly from their base so that after they are bent the axially extending fingers are located radially outwardly of the periphery of the disk l5 a distance at least as great as their thickness. A fragmentary front view of the disk l5 after it has been subjected to the bending operation illustrated in Figure 7 is shown in Figure 8.

The disk as shown in Figures 7 and 8 is in finished form as a supporting web and is ready for assembly with the brake ring. As previously mentioned, the fingers H3 are of the same shape as the openings M but are somewhat smaller in cross. sectional area. In assembling the web and ring the fingers l6 are inserted into the openings M as shown in Figure 10. The web and ring are permanently fastened to each other by flowing the metal at the free extremities of fingers it. This is done as illustrated in Figure 11. As there shown the ring and web in assembled relation are supported by a fixture 31]. This fixture supports the web against both radial and axial displacement. The metal in the fingers i5 is flowed by applying axial pressure against the free extremities thereof with a specially formed punch 3|. By applying axial pressure to the ends of the fingers IS the metal of the fingers is caused to flow ain'ally to a sufi'icient extent to completely fill the openings i l in the flange ll. By reason of the special contour of the punch M the metal is caused to flow radially and circumferentially as well as axially.

It is desirable to flow the metal of the fingers l6 axially so as to completely fill the openings l4 and thereby to prevent movement between the ring and web and also to provide adequate heat transfer from the ring to the web. It is necessary to flow the metal of fingers l6 radially and circumferentially because it is desired to enlarge the ends of fingers i6 sufficiently to completely overlie the edges of the openings I4 through which the fingers extend. This is desired in order to assure the proper connection between the ring and web and to further facilitate the dissipation of heat from the ring to the web. The manner and extent of the enlargement of the finger ends is clearly shown at ll in Figures 13 and 14.

By making the Web US with an overall diameter less, than the diameter of the brake ring a considerable saving in material results. By utilizing the integral fingers lfifor fastening the web and ring together the number of parts employed is maintained at a minimum and at the same time a very eflicient heat transferring connection is provided. The manner in which the ends of fingers i6 are enlarged insures a secure connection between the web and ring and one which will withstand without destruction or distortion any use to which the drum is usually subjected. All.

these advantages are obtained at a minimum of expense.

The scope of the invention, which may be em bodied in modifications other than those shown and described, is indicated in the appended claims.

I claim:

1. The method of manufacturing brake drums including a brake ring having a radial flange provided with circumferentially spaced apertures, which comprises: forming a disk-like supporting web for the ring having a main diameter locating its periphery inwardlyof said ring apertures and having integral projections extending beyond its periphery, assembling the ring and web with the projections of the latter extending through the apertures in the flange of the former, and flowing the metal of said projections in radial and axial directions from the free extremities thereof to completely fill the cooperating apertures through which they extend and to overlie the edges thereof.

2. The method of manufacturing brake drums including a brake ring having a radial flange, which comprises: forming a plurality of circumferentially spaced openings in the flange, forming a disk-like supporting web with a plurality of integral projections at its periphery, said projections being of the same cross sectional configuration but slightly smaller than the apertures in the ring flange, assembling the web and ring with the projections of the former extending through the apertures in the flange of the latter, and flowing the metal of said projections in axial, radial and circumferential directions to completely fill the cooperating apertures and to overlie the edges thereof.

HARRY J. I-llO-RN. 

